JP2553750B2 - Magneto-optical disk device - Google Patents

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magneto-optical disk device capable of both overwriting of a magneto-optical disk of a magnetic field modulation overwrite type and recording / reproducing erasing of a magneto-optical disk requiring a conventional erasing process. Is. 2. Description of the Related Art In recent years, magneto-optical disk devices capable of recording information signals at high density are being used. This is thought of as a magneto-optical disk device which generally uses an alloy of a rare earth and a transition metal as a recording medium and requires three processes of erasing, recording, and reproducing, and a magneto-optical disk device capable of overwriting by a magnetic field modulation method. Has been. Recording of the above-described conventional magneto-optical disk device will be described below with reference to the drawings.
FIG. 6 is a schematic view of a conventional magneto-optical disk device (conventional example 1) which requires three processes of erasing, recording and reproducing. In FIG. 6, reference numeral 1 is a magneto-optical disk, on which a magneto-optical recording layer 3 is formed on a substrate 2 by a thin film forming means such as sputtering. Reference numeral 4 is a magnetic field generator composed of a magnet or an electromagnet, 5 is a laser beam, and 6 is an objective lens for focusing the laser beam of 5. The operation of the conventional magneto-optical disk and the recording method thereof configured as described above will be described below. The direction of magnetization of the magneto-optical recording layer 3 on the substrate 2 is previously aligned in one direction during the erasing process. When a magnetic field is applied to the magneto-optical disk 1 by a magnetic field generator 4 and the magneto-optical recording layer 3 is heated by the laser beam 5 focused by the objective lens 6 to a temperature near the Curie temperature or higher, the magneto-optical recording layer 3 is cooled. The magnetization is changed and fixed according to the direction of the magnetic field, and the recording process is achieved. In reality, the laser beam 5 is an on / off signal modulated with a recording signal, so the magnetization of the magneto-optical recording layer 3 is reversed only when heated. To erase the recording medium thus written, that is, to align the magnetization direction of the magneto-optical recording layer 3 in one direction, 4
This is achieved by inverting the magnetic field of the magnetic field generator and irradiating the laser beam 5 of continuous light. The regeneration process is
The fact that the Kerr rotation angle of the reflected light changes according to the direction of magnetization by irradiating continuous laser light whose intensity is a fraction of that at the time of recording is used. In the case of the above-described magneto-optical disk device, when rewriting, it is necessary to erase the previously written information in advance and then record it. Therefore, much time is required for recording information. In order to eliminate this drawback, overwrite technology is currently being actively researched. One of these methods is called the magnetic field modulation method.
It is proposed in JP-A-60-48806. This magnetic field modulation method is also used in the magneto-optical disk device for data files,
There is proposed a device capable of recording data at high speed by using a magnetic field generating means (flying magnetic head) capable of floating and sliding on a magneto-optical disk. Recording in the magneto-optical disk device (conventional example 2) of the magnetic field modulation type overwrite will be described below with reference to FIG. In FIG. 7, reference numeral 7 denotes a magneto-optical disk corresponding to a magnetization modulation overwrite, and a magneto-optical recording layer 3 is formed on a substrate 2 by a thin film forming means such as sputtering. Furthermore, a special overcoat layer 8 is provided on the magneto-optical disk for magnetic field modulation overwriting using a flying magnetic head. Reference numeral 5 is a laser beam, 6 is an objective lens for focusing the laser beam of 5, 9 is a flying magnetic head, and 10 is a magnetic head current drive circuit. When the magneto-optical disk is stopped, the flying magnetic head 9 and the magneto-optical disk 7 are in contact with each other, and when the magneto-optical disk is rotating, the flying magnetic head 9 floats above the special overcoat layer 8 by several μm. That is, the contact start stop (CSS) method is used.
For recording, the magneto-optical recording layer 3 is heated to near the Curie temperature by a laser beam 5 continuously emitted, and at the same time, a modulation magnetic field is applied by a flying magnetic head 9 to the vicinity of the heated portion.
The magnetization of the heated magneto-optical recording layer 3 is reversed according to the direction of the modulation magnetic field, and the direction of the magnetization is fixed when the magneto-optical recording layer 3 is cooled, and the information is recorded as information. In the case of the conventional example 2, since the magneto-optical recording layer is heated when rewriting, even if information has already been written on the recording track, the previous information disappears at the same time as the writing, and is overwritten by new information. Is made. However, the magneto-optical disk device of the above-mentioned conventional example 1 requires an erasing process for erasing previous information in advance when recording, and naturally there is no overwrite function, while the conventional example does not. The second magneto-optical disk device is compatible with overwrite, but a magneto-optical disk with a special overcoat must be used because of CSS. At present, the commercialization of the conventional example 1 is underway, and the conventional example 2 which can be overwritten as the next generation is in the development stage. In this case, the problem is that the magneto-optical disk of Conventional Example 1 cannot be used in the next-generation model of Conventional Example 2 because it is not considering applying a special overcoat corresponding to CSS. In the case of a data file, it is important that information written on a previous generation (conventional example 1) model can be read and written on a next-generation model (conventional example 2), and a magneto-optical disk for conventional example 1 is also used in the device of conventional example 2. It was hoped that it could be done. In view of the above problems, the present invention can perform conventional recording / reproducing / erasing on a magneto-optical disk that requires a conventional erasing process. An object of the present invention is to provide a magneto-optical disk device that enables the operation. Means for Solving the Problems In order to solve the above problems, the magneto-optical disk device of the present invention generates a magnetic field in the recording signal frequency band as a means for applying a magnetic field to the magneto-optical disk, and aerodynamic effects on the magneto-optical disk. The first magnetic field generator having a structure capable of levitating and sliding by the N and S without contact with the magneto-optical disk.
A second magnetic field generator capable of generating a DC magnetic field of both poles, the both magnetic field generators being movable in a direction parallel to the magneto-optical disk, and the relative positional relationship between the two magnetic field generators is The first magnetic field generator is attached to the transfer driving means that is movable in the radial direction of the disc so that the first magnetic field generator is on the outer peripheral side or the inner peripheral side of the second magnetic field generator, and the first magnetic field generator is optically driven. It is composed of vertical drive means that can come into contact with the surface of the magnetic disk. Further, it is possible to selectively apply the magnetic field from the first magnetic field generator or the second magnetic field generator to the magneto-optical disk by judging the magneto-optical disk type. Or as a means to give a magnetic field to the magneto-optical disk,
A magnetic field generator having a first magnetic field generator capable of generating a magnetic field in the recording signal frequency band and a second magnetic field generator capable of generating a DC magnetic field of both N and S poles is integrated. Has a structure that allows the device to levitate and slide on the magneto-optical disk by an aerodynamic effect, and the first magnetic field generating section and the second magnetic field generating section are provided apart from each other in the radial direction of the magneto-optical disk. The container is attached to a movable driving means, and further comprises a vertical driving means capable of abutting on the surface of the magneto-optical disk. Also, by the magneto-optical disk type judgment,
The magnetic field from the first magnetic field generator or the second magnetic field generator can be selectively applied to the magneto-optical disk. Action With this configuration, the magneto-optical disk that is installed first
It is determined whether or not the magneto-optical disk is compatible with magnetic field modulation. In the case of the magneto-optical disk compatible with magnetic field modulation, a first magnetic field generator having a structure capable of levitating and sliding on the magneto-optical disk by an aerodynamic effect, or A magnetic field generator having both the first and second magnetic field generators is brought into contact with the surface of the magneto-optical disk by the vertical driving means, and levitates while the magneto-optical disk rotates. Then, the laser beam of the optical head is moved onto the heated recording track of the magneto-optical recording layer by the driving means capable of moving in the direction parallel to the magneto-optical disk, and the first magnetic field generator or the first magnetic field is generated. Overwriting is performed by the modulation magnetic field from the generator. In the case of a conventional magneto-optical disk that requires an erasing process, the magneto-optical disk surface can be used in either case of the second magnetic field generator or the magnetic field generator having both the first and second magnetic field generating sections. It is lifted by the vertical driving means so that it does not come in contact with the top. As the magnetic field required for erasing and recording, the magnetic field from the second magnetic field generator or the second magnetic field generator is used. Second
If the magnetic field generator or the second magnetic field generator is an electromagnet, it is transferred to a desired track by a transfer means parallel to the magneto-optical disk, and the current polarity is switched between erasing and recording. When the second magnetic field generator or the second magnetic field generator is a permanent magnet having both N and S poles, it is parallel to the magneto-optical disk so that the necessary magnetic field polarities can be obtained during erasing or recording. The N-pole or the S-pole is moved onto the track to be erased or recorded by the transfer driving means in different directions, and the erase or recording is performed. Embodiment A magneto-optical disk device according to an embodiment of the present invention will be described below with reference to the drawings.

Embodiment 1 FIGS. 1A and 1B are a plan view and a side view of the basic configuration of a magneto-optical disk device according to Embodiment 1 of the present invention. 1 (c) and 1 (d) are partial sectional views showing the structure of the magneto-optical disk, and FIGS. 2 and 3a, b, and c are the first magnetic field generator and the second magnetic field generation, respectively. It is a perspective view and a schematic diagram for explaining a container. Figure 1 (a) (b)
(C) (d) or in each of FIGS. 2 and 3,
1 is a magneto-optical disk, 2 is a substrate, 3 is a magneto-optical recording layer, 11
Is a normal overcoat layer, and 8 is a special overcoat layer. In the case of the magneto-optical disk requiring the erasing process described in Conventional Example 1, an ultraviolet curable resin is generally used for the overcoat layer, while the magneto-optical disk compatible with the magnetic field modulation overwrite is CSS compatible. A resin obtained by kneading an abrasive and a lubricant in an ultraviolet curable resin, or a thin film such as DIC (diamond-like carbon) is used. In the actual magneto-optical disk, in addition to these layers, the layers are further multi-layered in order to adjust the sensitivity, increase the Kerr rotation angle, or enhance the weather resistance of the magneto-optical disk. Each layer is omitted. Next, 12 is a spindle motor, 6 is an objective lens of an optical head (not shown), 5 is a laser beam, 13 is its focused spot, 14 is a magnetic field in the recording signal frequency band,
It is a first magnetic field generator having a structure capable of levitating and sliding on a magneto-optical disk by an aerodynamic effect. FIG. 2 is a perspective view of the detailed structure of the monolithic type in which the slider portion and the magnetic circuit are made of the same magnetic material. In the figure, 15 is a slider part for floating and sliding on the magneto-optical disk by an aerodynamic effect, 16 is a coil, 17 is a magnetic gap, 18 is a main pole, 19 is a magnetic field, and 20 is a first magnetic field generator. And a load beam for abutting this magnetic field generator on the magneto-optical disk 1. The end of the load beam 20 is joined to the movable portion 23 of the transfer driver 22 via the leaf spring 21 so that the tilt angle of the load beam 20 can be changed with respect to the movable portion 23. Next, 24 is a second magnetic field generator capable of generating DC magnetic fields of both N and S poles. The second magnetic field generator 24 may be a permanent magnet type shown in FIG. 3a, a single-pole type DC electromagnet type shown in FIG. 3b, or a two-pole type shown in FIG. 3c facing the magneto-optical disk surface. There are various types of DC electromagnet type. In each of FIGS. 3a, 3b and 3c, 25 is a permanent magnet having both N and S magnetic poles, 26 is a magnetic core, 27 is a coil, and L is a distance between magnetic poles. Reference numeral 28 denotes a rigid support arm for supporting the second magnetic field generator, which is also joined to the movable portion 23 of the transfer driver 22, and in any of these FIGS. By moving the second magnetic field generator in a direction parallel to the magneto-optical disk, or by moving it and switching the current polarity of the electromagnet, an N magnetic field or an S magnetic field can be applied on an arbitrary track of the magneto-optical disk. . Magneto-optical disk 1
When there is no surface wobbling, the second magnetic field generator 24 supported by the support arm 28 keeps a constant gap with the magneto-optical disk. Actually, the surface wobbling of the magneto-optical disk is also taken into consideration. However, a gap of about 1 mm is provided. 29 is a transfer driver 22
It is a fixed part of. The transfer driver 22 is a linear motor, a linear stepping motor, or the like, in which the movable portion 23 can slide relative to the fixed portion 29, and the first or second magnetic field is generated from the innermost track position to the outermost track position of the magneto-optical disk 1. The vessels 14 and 24 can be moved. Reference numeral 30 denotes a load beam supporting arm joined to the load beam 20, and the movement of the magnetic field generator raising and lowering plate 32 that rotates in the direction indicated by the arrow 31 causes the load beam 20 to be raised and lowered, that is, the first magnetic field generator.
The contact and the disengagement of 14 with the magneto-optical disk 1 are performed. The operation of the magneto-optical disk device configured as described above will be described below. First, when the magneto-optical disk 1 is mounted on the magneto-optical disk device or at the mounting stage, the magneto-optical disk 1 requires an erasing process. It is determined whether or not the magneto-optical disk is compatible with the magnetic field modulation overwrite by the identifier of the magneto-optical disk cartridge case (for example, the presence or absence of an identification concave portion specially provided in the cartridge case). When it is determined to be the magneto-optical disk of the type of Conventional Example 1, the magnetic field generator raising / lowering plate 32 is the load beam supporting arm.
Keep 30 pulled up. Therefore the first
The magnetic field generator 14 does not contact the magneto-optical disk 1. The first magnetic field generator 14 is not used for this magneto-optical disk, but the second magnetic field generator 24 is used. Although the gap between the second magnetic field generator 24 and the magneto-optical disk 1 is about 1 mm, the second magnetic field generator 24 can obtain a sufficient magnetic field for recording and erasing on the magneto-optical disk. In the case where the magneto-optical disk device is a data file device, after the magneto-optical disk 1 enters the steady rotation state, the controller built in the magneto-optical disk device generally performs a series of initial operations in a state in which recording, reproduction and erasing can be performed. Next, the operation of the objective lens 6 of the optical head and the movable portion 23 of the transfer driver 22 in the case where an arbitrary nth track is accessed and that track is reproduced or recorded will be described. In the case of reproducing now, the focused spot 13 of the laser beam 5 is n by the transfer of the optical head itself (however, the transfer means of the optical head is not shown) and the fine movement of the objective lens 6.
Access is made on the th track and the signal is reproduced. Next, in the case of recording or erasing, the focused spot 13 of the laser beam 5 is accessed on the n-th track as in the case of reproduction, and at the same time, the second drive unit 22 drives the second magnetic field generator 24 to drive the n-th track. Move to the vicinity of the second track.
In the case where the second magnetic field generator 24 is a permanent magnet type having N and S2 poles shown in FIG. 3a, the position where the magnetic field from the N pole is given in recording (the magnetic field from the N pole to the magneto-optical disk). Is referred to as an N magnetic field, and is assumed to be a magnetic field at the time of recording. The magnetic field at the time of erasing is assumed to be an S magnetic field). 22 drives a second magnetic field generator 24. That is, during recording and erasing, the movable portion 23 of the transfer driver 22 moves in the radial direction of the magneto-optical disk 1 by the distance L between the magnetic poles, and the set position changes. Next, at the time of recording, the laser beam 5 modulated by the recording signal heats the magneto-optical recording layer 3 under the above N magnetic field applied state to the magneto-optical disk 1, and the signal is written. At the time of erasing, a continuous laser beam 5 continuously heats the magneto-optical recording layer 3 under an S magnetic field applied state, and erasing is performed. When recording and erasing are performed alternately, the condensed spot 13 of the objective lens 6 remains on the same track, but the transfer driver 22
The movable part 23 moves forward and backward to alternately apply N and S magnetic fields to the magneto-optical disk 1. In the case of the single pole type DC electromagnet type shown in FIG. 3b, the magnetic pole portion at the tip moves to the vicinity of the nth track, the polarity of the coil current is switched, and the required magnetic field of N or S is magneto-optical. It is given to the disc 1. Further, in the case of the U-shaped electromagnet type in which the two poles shown in FIG. 3C face the magneto-optical disk surface, only one magnetic pole of the U-shaped electromagnet is used,
A method of switching the polarity of the magnetic pole by switching the polarity of the coil current, or a transfer driver in the radial direction of the magneto-optical disk by a distance corresponding to the distance L between the magnetic poles so that the other magnetic pole is used without switching the polarity of the current. There is a method of moving the movable part 23 of 22 to obtain the required magnetic field of N or S. Of course, this is the design of the device and either is possible. Next, when it is determined that the mounted magneto-optical disk 1 is a magneto-optical disk compatible with the magnetic field modulation overwrite of Conventional Example 2, the magnetic field generator raising / lowering plate 32 is rotated. Along with this, the lifted state of the load beam support arm 30 is released, and the first magnetic field generator 14 contacts the special overcoat 8 of the magneto-optical disk 1. The second magnetic field generator 24 is not used for this magneto-optical disk, but the first magnetic field generator 14 is used.
To use. The first magnetic field generator 14 is designed to have a magnetic circuit configuration capable of generating a magnetic field in the recording signal frequency band, that is, an inductance of several μH or less. Next, the magneto-optical disk 1 starts to rotate, and the slider portion 15 starts to slide on the magneto-optical disk 1. When the rotation speed of the magneto-optical disk exceeds a certain value, the levitation sliding state due to the aerodynamic effect is entered, and when the magneto-optical disk enters the steady rotation state,
It will be in a stable levitating condition. Similar to the above, the controller built in the magneto-optical disk device performs a series of initial operations,
Playback and overwrite can be performed. The operation of the optical head when reproducing or overwriting is performed on an arbitrary n-th track is the same as described above. However, in the case of overwriting, the laser beam 5 is continuous light. When overwriting is performed on the n-th track, the main magnetic pole 18 of the first magnetic field generator 14 is driven by the n-th magnetic pole by driving the transfer driver 22 in order to apply the recording magnetic field modulated by the signal to the magneto-optical disk 1. Move to the vicinity of the second track. The modulation signal current is supplied to the coil 16, and a magnetic field 19 corresponding to the modulation signal is generated to perform overwriting. Next, the transfer driver during regeneration
Touch on 22 actions. When roughly divided, the first and second magnetic field generators 14 and 24 are always located at the same set position on the magneto-optical disk as when the transfer driver 22 is driven according to the reproduction track during reproduction. There are cases.
In the former case, the drive distance of the transfer driver 22 becomes comparatively short when the recording / erasing or overwriting state is changed from the reproduction state, and in the latter case, the power consumption during reproduction can be reduced. In addition to this, the playback status or recording, erasing,
Alternatively, the first and second magnetic field generators 1 after overwriting
Various cases can be considered regarding how to set the setting positions of 4 and 24. After the recording, the recording is often performed on the track in the vicinity of the recording, and therefore the transfer driver 22 may not be moved from that position for a while after the recording.
In any case, the movement mode of the magnetic field generator can be determined based on the design policy of the magneto-optical disk device. As described above, according to the present embodiment, as a means for applying a magnetic field to the magneto-optical disk, a first magnetic field is generated which has a structure capable of generating a magnetic field in the recording signal frequency band and levitating and sliding on the magneto-optical disk by the aerodynamic effect. The second device that can generate the DC magnetic fields of both N and S poles without making contact with the magneto-optical disk
Of the magnetic field generator, and the two magnetic field generators can be moved in the direction parallel to the magneto-optical disk. The relative positional relationship between the two magnetic field generators is that the first magnetic field generator is the second magnetic field generator. A transfer driving unit that is movable in the radial direction of the disk so as to be on the outer peripheral side or the inner peripheral side of the disk with respect to the magnetic field generator;
By selectively using both the magnetic field generators according to the type of the magneto-optical disk by the vertical drive means capable of abutting the magnetic field generator on the surface of the magneto-optical disk, the apparatus of the present embodiment is provided with the magnetic field modulation overwrite. Not only compatible magneto-optical discs,
A conventional magneto-optical disk that requires an erasing process can also be recorded, reproduced, and erased.

Second Embodiment FIGS. 4 (a) and 4 (b) are a plan view and a side view of the basic configuration of a magneto-optical disk device according to a second embodiment of the present invention. FIG. 5 is a perspective view of the magnetic field generator used in this embodiment. In each of FIGS. 4 and 5, 1 is a magneto-optical disk, which is provided with an ordinary overcoat layer or a special overcoat layer as in the first embodiment. Next, 12 is a spindle motor, 6 is an objective lens of an optical head (not shown), 5 is a laser beam, 13 is a focused spot thereof, and 33 is a first magnetic field generator capable of generating a magnetic field in the recording signal frequency band. And a second magnetic field generating section capable of generating a DC magnetic field of both N and S poles, and having a structure capable of levitating and sliding on the magneto-optical disk by an aerodynamic effect. FIG. 5 shows a perspective view of the detailed structure. The slider part is a composite type that uses a non-magnetic material, and is a slider part for floating and sliding on the magneto-optical disk by the aerodynamic effect.
34, a first magnetic field generating section 35 for generating a magnetic field in the recording signal frequency band, a second magnetic field for generating a DC magnetic field of both N and S poles
Of the magnetic field generation unit 36. First magnetic field generator 35
Has a magnetic circuit configuration capable of generating a magnetic field in the recording signal frequency band, that is, a magnetic circuit having an inductance of several μH or less, and has a first coil 37, a first magnetic pole 38, and a second magnetic pole 39. First magnetic core 40, first magnetic gap
41, which generates a magnetic field 42. The second magnetic field generating unit 36 includes a second coil 43, a second magnetic core 46 having a third magnetic pole 44 and a fourth magnetic pole 45, and a second magnetic gap 47, and generates a magnetic field 48. Reference numeral 20 is a load beam for supporting the magnetic field generator 33 and for abutting the magnetic field generator 33 on the magneto-optical disk 1. Its end is a transfer driver via a leaf spring 21.
It is joined to the movable part 23 of 22 and the load beam is attached to the movable part 23.
It has a structure that can change the tilt angle of 20. 29 is a fixed portion of the transfer driver 22. This fixed part is movable part
23 is movable with respect to the magneto-optical disk 1 in the same manner as in the first embodiment. Reference numeral 30 is a load beam supporting arm joined to the load beam 20, and 32 is a magnetic field generator raising / lowering plate, the function of which is the same as that of the first embodiment. The second embodiment is different from the first embodiment in that the magnetic field generating means for the recording signal frequency band and the DC magnetic field generating means are integrated. The operation of the second embodiment configured as described above will be described. However, regarding the functions and operations, the same parts as those in the first embodiment will be omitted. First, when the magneto-optical disk 1 is mounted on the magneto-optical disk device, or at the mounting stage, the type of the magneto-optical disk 1 is determined by the same means as in the first embodiment. When it is determined that the magneto-optical disk is of the type of Conventional Example 1, the magnetic field generator raising / lowering plate 32 keeps the load beam supporting arm 30 in the raised state. Therefore, the magnetic field generator 33 does not contact the magneto-optical disk. For this magneto-optical disk, the first of the magnetic field generator 33
The magnetic field generator 35 is not used, but the second magnetic field generator 36 is used. When the magneto-optical disk 1 is free of surface wobbling, the distance between the magnetic field generator 33 and the magneto-optical disk 1 is always kept constant.
Pull up the load beam 20 so that there is a gap of about m. As described in the first embodiment, the controller built in the magneto-optical disk device performs a series of initial operations. Next, an arbitrary nth track is accessed, and the access of the optical head when recording / reproducing that track is also the same as in the first embodiment. In the case of recording or erasing, the third magnetic pole 44 of the magnetic field generator 33 is moved to the vicinity of the nth track by driving the transfer driver 22 at the same time as the access of the optical head. In the recording, the third magnetic pole 44 is the N magnetic pole,
In erasing, the current magnetism of the second coil 43 is switched so that the S magnetic pole is obtained, and recording or continuous laser beam 5 is performed with the laser beam 5 modulated by the recording signal under application of the magnetic field 48.
To erase. In the above case, only the third magnetic pole 44 is used, and the current magnetism of the second coil 43 is switched to obtain the N and S magnetic fields. However, the current magnetism of the second coil 43 is not switched, and the third magnetic pole is used for recording. There is a method of using the magnetic pole 44 and a fourth magnetic pole 45 for erasing. In this case, the transfer driver 22
The movable portion 23 is moved back and forth to move the third magnetic pole 44 or the fourth magnetic pole 45 to the vicinity of the nth track. Furthermore, in the above case, the second magnetic field generator 35 uses an electromagnet, but N,
A permanent magnet having S poles may be arranged in the second magnetic core portion. In this case, it is necessary to move the movable portion 23 of the transfer driver 22 back and forth for recording and erasing, as in the case of the first embodiment. When it is determined that the attached magneto-optical disk 1 is a magneto-optical disk compatible with the magnetic field modulation overwrite of Conventional Example 2, the magnetic field generator raising / lowering plate 32 rotates and the magnetic field generator 33 causes the magneto-optical disk 1 to move. Abut on the special overcoat layer.
The second magnetic field generator 36 is not used for this magneto-optical disk, but the first magnetic field generator 35 is used. Magneto-optical disk 1
With the rotation, the slider portion 34 starts to slide on the magneto-optical disk 1, and when in a steady rotation state, it is in a stable floating and gliding state. When the n-th track is overwritten, the recording magnetic field modulated by the signal is applied to the magneto-optical disk 1.
The magnetic field generator 33 is driven by the transfer driver 22 in order to
The first magnetic pole 38 is moved to the vicinity of the nth track. The modulation signal current is supplied to the first coil 37, a magnetic field 42 corresponding to the modulation signal is generated, and overwrite is performed. The operation of the transfer driver 22 during reproduction or after overwriting can be determined based on the design policy of the magneto-optical disk device, as in the first embodiment. As described above, according to the present embodiment, as the means for applying the magnetic field to the magneto-optical disk, the first magnetic field generating section capable of generating the magnetic field in the recording signal frequency band and the DC magnetic field having both N and S poles can be generated. It has a magnetic field generator integrated with the second magnetic field generator, and this magnetic field generator has a structure capable of floating and sliding on the magneto-optical disk by the aerodynamic effect. Moreover, this magnetic field generator is a magneto-optical disk. Since it has a magnetic field generator vertical drive means that is attached to the drive means that can be moved in the radial direction and that can contact the surface of the magneto-optical disk, both magnetic field generation sections can be selectively selected according to the type of the magneto-optical disk. The device of this embodiment is capable of recording, reproducing and erasing not only the magneto-optical disk corresponding to the magnetic field modulation overwrite but also the conventional magneto-optical disk requiring the erasing process. In the case of this embodiment, the first magnetic field generator and the second magnetic field generator
Since the magnetic field generator is integrated with the magnetic field generator, the overall size of the magnetic field generator can be made smaller than that of the first embodiment, and the magnetic field generator can easily enter the window of the cartridge case. In addition, since the first magnetic field generating unit and the second magnetic field generating unit are integrated, the movable range of the transfer driver can be shorter than that of the first embodiment.
It is possible to make the size smaller than that of the transfer driver. Advantageous Effects of Invention The magneto-optical disk device of the present invention has, as a means for applying a magnetic field to the magneto-optical disk, a structure capable of generating a magnetic field in the recording signal frequency band and levitating and sliding on the magneto-optical disk by the aerodynamic effect. Magnetic field generator and a second magnetic field generator capable of generating DC magnetic fields of both N and S poles, both magnetic field generators being movable in a direction parallel to the magneto-optical disk, and generating both magnetic fields. The relative positional relationship of the devices is such that the first magnetic field generator is attached to the transfer drive means that is movable in the radial direction of the disc so that the first magnetic field generator is on the outer peripheral side or the inner peripheral side of the disc with respect to the first magnetic field generator. , And a vertical drive means capable of abutting the first magnetic field generator on the surface of the magneto-optical disk. Therefore, by selectively using both magnetic field generators according to the type of magneto-optical disk, not only magneto-optical disks compatible with magnetic field modulation overwrite but also conventional magneto-optical disks requiring an erasing process can be recorded, reproduced, and erased. It is possible to As means for applying a magnetic field to the magneto-optical disk, a first magnetic field generating section capable of generating a magnetic field in the recording signal frequency band and a second magnetic field generating section capable of generating a DC magnetic field of both N and S poles are integrated. The magnetic field generator has a structure that allows the magnetic field generator to levitate and slide on the magneto-optical disk by the aerodynamic effect, and the magnetic field generator can be moved in the radial direction of the magneto-optical disk. Since it has an up-and-down driving means that can be contacted with the surface of the magneto-optical disk, it is possible to selectively use both of the magnetic field generating portions according to the type of the magneto-optical disk, and thus the magneto-optical disk of the present invention. The device can record, reproduce, and erase not only a magneto-optical disk compatible with magnetic field modulation overwrite, but also a conventional magneto-optical disk requiring an erasing process. Further, since the first magnetic field generator and the second magnetic field generator are integrated, the size of the entire magnetic field generator can be reduced, and the magnetic field generator can easily enter the window of the cartridge case. Further, since the first magnetic field generator and the second magnetic field generator are integrated, the movable range of the transfer driver can be shortened, and the transfer driver can be downsized.

[Brief description of drawings]

1 (a) and 1 (b) are a plan view and a side view of the basic structure of a magneto-optical disk device according to a first embodiment of the present invention, and FIGS. 1 (c) and 1 (d) are structures of a magneto-optical disk. 2 is a perspective view of a first magnetic field generator used in the first embodiment, and FIGS. 3a, 3b, 3c are schematic views showing an example of the second magnetic field generator, and FIG. (A) and (b) are a plan view and a side view of a basic configuration of a magneto-optical disk device according to a second embodiment of the present invention, and FIG. 5 is a perspective view of a magnetic field generator used in the second embodiment. FIG. 1 is a schematic view of a conventional magneto-optical disk device requiring an erasing process, and FIG. 7 is a schematic view of a conventional magnetic field modulation type overwrite magneto-optical disk device. 1 ... Magneto-optical disk, 2 ... Substrate, 3 ... Magneto-optical recording layer, 4 ... Magnetic field generator, 5 ... Laser beam, 6 ... Objective lens, 7 ... Magneto-optical disk compatible with magnetic field modulation overwrite , 8: Special overcoat layer, 9: Flying magnetic head, 10: Magnetic head current drive circuit, 11: Normal overcoat layer, 12: Spindle motor, 13: Focus spot, 14: No. 1 magnetic field generator, 15 ... slider part, 16 ... coil, 17 ... magnetic gap, 18 ... main pole, 19 ... magnetic field, 20 ... load beam, 21 ... leaf spring,
22 …… Transport driver, 23 …… Movable part, 24 …… Second magnetic field generator, 25 …… Permanent magnet, 26 …… Magnetic core, 27 …… Coil, L …… Distance between magnetic poles, 28 …… Support arm, 29 ... Fixed part, 30 ... Load beam support arm, 31 ... Arrow, 32 ...
… Magnetic field generator raising / lowering plate, 33 …… Magnetic field generator, 34 …… Slider section, 35 …… First field generating section, 36 …… Second magnetic field generating section, 37 …… First coil, 38 …… First magnetic pole, 39 ... Second magnetic pole, 40 ... First magnetic core, 41 ... First magnetic gap, 42 ... Magnetic field, 43 ... Second coil, 44 ... Third magnetic pole,
45 …… 4th magnetic pole, 46 …… Second magnetic core, 47 …… Second magnetic gap, 48 …… Magnetic field.

Claims (4)

(57) [Claims] 1. A first structure having a structure capable of generating a magnetic field in a recording signal frequency band and flying and sliding on the magneto-optical disk by an aerodynamic effect, as means for applying a magnetic field to the magneto-optical disk.
Magnetic field generator and a second magnetic field generator capable of generating a DC magnetic field of both N and S poles that are not in contact with the magneto-optical disk, and both magnetic field generators are parallel to the magneto-optical disk. In the radial direction of the disk so that the first magnetic field generator is on the outer peripheral side or the inner peripheral side of the disk with respect to the second magnetic field generator. A magneto-optical disk device equipped with a vertical drive means attached to a movable transfer drive means and capable of abutting the first magnetic field generator on the surface of the magneto-optical disk. 2. The magneto-optical disk according to claim 1, wherein the magnetic field from the first magnetic field generator or the second magnetic field generator is selectively applied to the magneto-optical disk. A magneto-optical disk device according to the item. 3. A first magnetic field generating section capable of generating a magnetic field in a recording signal frequency band and a second magnetic field generating section capable of generating a DC magnetic field of both N and S poles as means for applying a magnetic field to a magneto-optical disk. And a magnetic field generator that is integrated with the magnetic field generator. The magnetic field generator has a structure capable of levitating and sliding on the magneto-optical disk by an aerodynamic effect. A magneto-optical disk apparatus which is provided separately in the radial direction of the magnetic disk, has the magnetic field generator attached to a movable driving means, and has vertical driving means capable of abutting on the surface of the magneto-optical disk. 4. The magneto-optical disk according to claim 3, wherein the magnetic field from the first magnetic field generating section or the second magnetic field generating section is selectively applied to the magneto-optical disk. A magneto-optical disk device according to the item.